Display device

ABSTRACT

A display device includes a display panel having a plurality of pixels connected to gate lines and data lines, and a plurality of fingerprint sensors connected to sensing lines and read-out lines. A gate driver provides gate signals to the gate lines and provides sensing signals to the sensing lines. The gate driver includes a first gate signal supply module providing a first gate signal to a first gate line among the gate lines. A first switching element is turned on by a reset enable signal to connect the first gate line and a first sensing line among the sensing lines.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. § 119 to Korean PatentApplication No. 10-2020-0159701, filed on Nov. 25, 2020 in the KoreanIntellectual Property Office, the disclosure of which is incorporated byreference in its entirety herein.

1. TECHNICAL FIELD

The present inventive concepts relate to a display device.

2. DISCUSSION OF RELATED ART

As the information society has developed, the demand for display devicesfor displaying images has diversified. For example, display devices havebeen applied to various electronic devices such as smart phones, digitalcameras, notebook computers, navigation systems, and smart televisions.Examples of display devices include flat panel display devices such as aliquid crystal display (LCD) device, a field emission display (FED)device, or an organic light-emitting diode (OLED) display device.

A display device may include a display panel for displaying an image, anoptical sensor for detecting light, a fingerprint sensor for detecting aperson's fingerprint, and the like. As display devices have been appliedto an increasing variety of electronic devices, the design of displaydevices has varied. For example, the display area of a display devicemay be widened by eliminating a sensor device such as an optical sensoror a fingerprint sensor.

SUMMARY

Embodiments of the present inventive concepts provide a display devicehaving a plurality of pixels and fingerprint sensors disposed in thesame layer therein and capable of increasing the duration of exposure ofthe fingerprint sensors to light even when hysteresis compensation isbeing performed.

However, embodiments of the present inventive concepts are notrestricted to those set forth herein. The above and other embodiments ofthe present inventive concepts will become more apparent to one ofordinary skill in the art to which the present inventive conceptspertain by referencing the detailed description of embodiments givenbelow.

According to an embodiment of the present inventive concepts, a displaydevice includes a display panel having a plurality of pixels connectedto gate lines and data lines, and a plurality of fingerprint sensorsconnected to sensing lines and read-out lines. A gate driver providesgate signals to the gate lines and sensing signals to the sensing lines.The gate driver includes a first gate signal supply module providing afirst gate signal to a first gate line among the gate lines. A firstswitching element is turned on by a reset enable signal to connect thefirst gate line and a first sensing line among the sensing lines.

In an embodiment, in response to the reset enable signal being receivedwhen the first gate signal has a gate-on level, the first switchingelement may, provide a reset signal to the first sensing line.

In an embodiment where the first gate signal may have the gate-on levelduring multiple horizontal scanning periods of a single frame, the resetenable signal may be provided to the first switching element during thefinal horizontal scanning period of the multiple horizontal scanningperiods.

In an embodiment, the first gate signal may have the gate-on level overa plurality of frames, and the reset enable signal may be provided tothe first switching element over at least one of the frames.

In an embodiment, the gate driver further may comprise a second gatesignal supply module providing a second gate signal to a second gateline among the gate lines, and a second switching element turned on by ascan enable signal to connect the second gate line to a second sensingline among the sensing lines.

In an embodiment, in response to the scan enable signal being receivedwhen the second gate signal has a gate-on level, the second switchingelement may provide a scan signal to the second sensing line.

In an embodiment in which the second gate signal has the gate-on levelduring multiple horizontal scanning periods of a single frame, the scanenable signal may be provided to the second switching element during thefinal horizontal scanning period of the multiple horizontal scanningperiods.

In an embodiment, each of the fingerprint sensors may comprise: alight-receiving element, a first sensor transistor providing a commonvoltage to a second node based on the voltage of a first node, the firstnode is a first electrode of the light-receiving element, a secondsensor transistor selectively connecting the second node and one of theread-out lines, and a third sensor transistor selectively providing areset voltage to the first node.

In an embodiment, the second sensor transistor may be turned on by thescan signal, and the third sensor transistor may be turned on by thereset signal.

In an embodiment, each of the pixels may comprise: a light-emittingelement, a first pixel transistor controlling a driving current that isto be provided to the light-emitting element, a second pixel transistorselectively providing a data voltage to a first node, the first node isa first electrode of the first pixel transistor, a third pixeltransistor selectively connecting a second node and a third node, thesecond node is a second electrode of the first pixel transistor, and thethird node is a gate electrode of the first pixel transistor, and afourth pixel transistor, which selectively provides an initializationvoltage to the third node.

In an embodiment, the second and third pixel transistors may be turnedon by the first gate signal, and the fourth pixel transistor may beturned on by the second gate signal.

In an embodiment, each of the pixels may further comprise: a fifth pixeltransistor selectively providing a driving voltage to the first node, asixth pixel transistor selectively connecting the second node and afourth node, the fourth node is a first electrode of the light-emittingelement, and a seventh pixel transistor selectively providing theinitialization voltage to the fourth node.

In an embodiment, the pixels may comprise first, second, and thirdpixels emitting light of different colors, the display panel maycomprise a plurality of unit pixel areas, and each of the unit pixelareas may comprise the first, second, and third pixels and at least onefingerprint sensor.

In an embodiment, the display panel may comprise: a substrate, athin-film transistor (TFT) layer disposed on the substrate, and alight-emitting element layer disposed on the thin-film transistor layer.The thin-film transistor layer may comprise: a gate insulating filmdisposed on the substrate, and an interlayer insulating film disposedon. the gate insulating film. Light-emitting elements of the pixels andlight-receiving elements of the fingerprint sensors may be disposed inthe light-emitting element layer.

In an embodiment, each of the pixels may comprise: an active area, asource electrode, and a drain electrode of a pixel transistor disposedon the substrate, a gate electrode of the pixel transistor disposed onthe gate insulating film, and a first connecting electrode disposed onthe interlayer insulating film and is connected to the drain electrodeof the pixel transistor.

In an embodiment, each of the light-emitting elements may comprise: apixel electrode disposed on the thin-film transistor layer and isconnected to the first connecting electrode, a light-emitting layerdisposed on the pixel electrode, and a common electrode disposed on thelight-emitting layer.

In an embodiment, each of the fingerprint sensors may comprise: anactive area, a source electrode, and a drain electrode of a sensortransistor disposed on the substrate, a gate electrode of the sensortransistor disposed on the gate insulating film, and a second connectingelectrode disposed on the interlayer insulating film and is connected tothe drain electrode of the sensor transistor.

In an embodiment, each of the light-receiving elements may comprise: asensor electrode disposed on the thin-film transistor layer and isconnected to the second connecting electrode, a light-receiving layerdisposed on the sensor electrode, and a common electrode disposed on thelight-receiving layer.

In an embodiment, the display panel may further comprise a displaydriver providing data voltages to the data lines and receives sensingsignals from the read-out lines.

In an embodiment, the gate lines and the sensing lines may extend in afirst direction and may be spaced apart from one another in a seconddirection intersecting the first direction. The data lines and theread-out lines may extend in the second direction and may be spacedapart from one another in the first direction.

According to an embodiment of the present inventive concepts, a displaydevice includes a display panel comprising a plurality of pixels havinglight-emitting elements and a plurality of fingerprint sensors havinglight-receiving elements. The light-emitting elements and thelight-receiving elements are disposed in a light-emitting element layerand are spaced apart from each other by a pixel defining film. A gatedriver provides gate signals to the plurality of pixels and sensingsignals to the plurality of fingerprint sensors. The gate driverprovides at least one gate signal having a gate-on level during aplurality of horizontal scanning periods of a single frame. The gatedriver provides at least one of a reset signal and a scan signal to theplurality of fingerprint sensors for activating the light-receivingelements, the at least one reset signal and scan signal are independentfrom the at least one gate signal.

According to the aforementioned and other embodiments of the presentinventive concepts, a plurality of pixels and a plurality of fingerprintsensors can be disposed in the same layer, and a gate driver can drivethe pixels based on a gate signal. As the gate signal has a gate-onlevel during multiple horizontal scanning periods of a single period, adisplay device can perform hysteresis compensation on the pixels. As thegate driver provides a reset signal and a scan signal, which areindependent from the gate signal, to the fingerprint sensors, the gatedriver can increase the duration of exposure of the fingerprint sensorsto light and increase the sensitivity of the fingerprint sensors, evenwhen the display device is performing hysteresis compensation.

Other features and embodiments may be apparent from the followingdetailed description, the drawings, and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other embodiments and features of the present inventiveconcepts will become more apparent by describing in detail embodimentsthereof with reference to the attached drawings, in which:

FIG. 1 is a perspective view of a display device according to anembodiment of the present inventive concepts;

FIG. 2 is an exploded perspective view of the display device of FIG. 1according to an embodiment of the present inventive concepts;

FIG. 3 is a plan view of a display panel of the display device of FIG. 1according to an embodiment of the present inventive concepts;

FIG. 4 is a plan view of a unit pixel area of the display device of FIG.1 according to an embodiment of the present inventive concepts;

FIG. 5 is a cross-sectional view of the display device of FIG. 1according to an embodiment of the present inventive concepts;

FIG. 6 is a cross-sectional view illustrating a thin-film transistor(TFT) layer and a light-emitting element layer of the display device ofFIG. 1 according to an embodiment of the present inventive concepts;

FIG. 7 is a layout view illustrating how pixels, fingerprint sensors,and lines of the display device of FIG. 1 are connected according to anembodiment of the present inventive concepts;

FIG. 8 is a block diagram illustrating how a gate driver, the pixels,and the fingerprint sensors of the display device of FIG. 1 areconnected according to an embodiment of the present inventive concepts;

FIG. 9 is a circuit diagram of a pixel of the display device of FIG. 1according to an embodiment of the present inventive concepts;

FIG. 10 is a circuit diagram of a fingerprint sensor of the displaydevice of FIG. 1 according to an embodiment of the present inventiveconcepts; and

FIG. 11 is a waveform view of signals applied to the pixel of FIG. 9 andthe fingerprint sensor of FIG. 10 according to an embodiment of thepresent inventive concepts.

DETAILED DESCRIPTION OF EMBODIMENTS

In the following description, for the purposes of explanation, numerousdetails are set forth to provide a thorough understanding of variousembodiments or implementations of the present inventive concepts. Asused herein “embodiments” and “implementations” are interchangeablewords that are non-limiting examples of devices or methods employing oneor more of the present inventive concepts disclosed herein. It isapparent, however, that various embodiments may be practiced withoutthese specific details or with one or more equivalent arrangements. Inother instances, well-known structures and devices are shown in blockdiagram form to avoid unnecessarily obscuring various embodiments.Further, various embodiments may be different, but do not have to beexclusive. For example, specific shapes, configurations, andcharacteristics of an embodiment may be used or implemented in anotherembodiment without departing from the present inventive concepts.

Unless otherwise specified, the illustrated embodiments are to beunderstood as providing non-limiting features of varying detail of someways in which the present inventive concepts may be implemented inpractice. Therefore, unless otherwise specified, the features,components, modules, layers, films, panels, regions, and/or aspects,etc. (hereinafter individually or collectively referred to as“elements”), of the various embodiments may be otherwise combined,separated, interchanged, and/or rearranged without departing from thepresent inventive concepts.

The use of cross-hatching and/or shading in the accompanying drawings isgenerally provided to clarify boundaries between adjacent elements. Assuch, neither the presence nor the absence of cross-hatching or shadingconveys or indicates any preference or requirement for particularmaterials, material properties, dimensions, proportions, commonalitiesbetween illustrated elements, and/or any other characteristic,attribute, property, etc., of the elements, unless specified. Further,in the accompanying drawings, the size and relative sizes of elementsmay be exaggerated for clarity and/or descriptive purposes. When anembodiment may be implemented differently, a specific process order maybe performed differently from the described order. For example, twoconsecutively described processes may be performed substantially at thesame time or in an order opposite to the described order. Also, likereference numerals denote like elements.

When an element, such as a layer, is referred to as being “on”“connected to,” or “coupled to” another element or layer, it may bedirectly on, connected to, or coupled to the other element or layer orintervening elements or layers may be present. When, however, an elementor layer is referred to as being “directly on,” “directly connected to,”or “directly coupled to” another element or layer, there are nointervening elements or layers present. To this end, the term“connected” may refer to physical, electrical, and/or fluid connection,with or without intervening elements. Further, the X-axis, the Y-axis,and the Z-axis are not limited to three axes of a rectangular coordinatesystem, such as the x, y, and z axes, and may be interpreted in abroader sense. For example, the X-axis, the Y-axis, and the Z-axis maybe perpendicular to one another, or may represent different directionsthat are not perpendicular to one another. For the purposes of thisdisclosure, “at least one of X, Y, and Z” and “at least one selectedfrom the group consisting of X, Y, and Z” may be construed as X only, Yonly, Z only, or any combination of two or more of X, Y, and Z, such as,for instance, XYZ, XYY, YZ, and ZZ. As used herein, the term “and/or”includes any and all combinations of one or more of the associatedlisted items.

Although the terms “first,” “second,” etc. may be used herein todescribe various types of elements, these elements should not be limitedby these terms. These terms are used to distinguish one element fromanother element. Thus, a first element discussed below could be termed asecond element without departing from the teachings of the presentinventive concepts.

Spatially relative terms, such as “beneath,” “below,” “under,” “lower,”“above,” “upper,” “over,” “higher,” “side” (e.g., as in “sidewall”), andthe like, may be used herein for descriptive purposes, and, thereby, todescribe one elements relationship to another element(s) as illustratedin the drawings. Spatially relative terms are intended to encompassdifferent orientations of an apparatus in use, operation, and/ormanufacture in addition to the orientation depicted in the drawings. Forexample, if the apparatus in the drawings is turned over, elementsdescribed as “below” or “beneath” other elements or features would thenbe oriented “above” the other elements or features, Thus, the exemplaryterm “below” can encompass both an orientation of above and below.Furthermore, the apparatus may be otherwise oriented (e.g., rotated 90degrees or at other orientations), and, as such, the spatially relativedescriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particularembodiments and is not intended to be limiting. As used herein, thesingular forms, “a,” “an,” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise. Moreover,the terms “comprises,” “comprising,” “includes,” and/or “including,”when used in this specification, specify the presence of statedfeatures, integers, steps, operations, elements, components, and/orgroups thereof, but do not preclude the presence or addition of one ormore other features, integers, steps, operations, elements, components,and/or groups thereof. It is also noted that, as used herein, the terms“substantially,” “about,” and other similar terms, are used as terms ofapproximation and not as terms of degree, and, as such, are utilized toaccount for inherent deviations in measured, calculated, and/or providedvalues that would be recognized by one of ordinary skill in the art.

Various embodiments are described herein with reference tocross-sectional and/or exploded illustrations that are schematicillustrations of idealized embodiments and/or intermediate structures.As such, variations from the shapes of the illustrations as a result,for example, of manufacturing techniques and/or tolerances, are to beexpected. Thus, embodiments disclosed herein should not necessarily beconstrued as limited to the particular illustrated shapes of regions,but are to include deviations in shapes that result from, for instance,manufacturing. In this manner, regions illustrated in the drawings maybe schematic in nature and the shapes of these regions may not reflectactual shapes of regions of a device and, as such, are not necessarilyintended to be limiting.

Some embodiments are described and illustrated herein in theaccompanying drawings in terms of functional blocks, units, and/ormodules. Those skilled in the art will appreciate that these blocks,units, and/or modules are physically implemented by electronic (oroptical) circuits, such as logic circuits, discrete components,microprocessors, hard-wired circuits, memory elements, wiringconnections, and the like, which may be formed using semiconductor-basedfabrication techniques or other manufacturing technologies. In anembodiment in which the blocks, units, and/or modules are implemented bymicroprocessors or other similar hardware, they may be programmed andcontrolled using software (e.g., microcode) to perform various functionsdiscussed herein and may optionally be driven by firmware and/orsoftware. It is also contemplated that each block, unit, and/or modulemay be implemented by dedicated hardware, or as a combination ofdedicated hardware to perform some functions and a processor (e.g., oneor more programmed microprocessors and associated circuitry) to performother functions. Also, each block, unit, and/or module of someembodiments may be physically separated into two or more interacting anddiscrete blocks, units, and/or modules without departing from the scopeof the present inventive concepts. Further, the blocks, units, and/ormodules of some embodiments may be physically combined into more complexblocks, units, and/or modules without departing from the scope of thepresent inventive concepts.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which the present inventive conceptspertain. Terms, such as those defined in used dictionaries, should beinterpreted as having a meaning that is consistent with their meaning inthe context of the relevant art and should not be interpreted in anidealized or overly formal sense, unless expressly defined herein.

FIG. 1 is a perspective view of a display device according to anembodiment of the present inventive concepts, FIG. 2 is an explodedperspective view of the display device of FIG. 1, and FIG. 3 is a planview of a display panel of the display device of FIG. 1.

Referring to the embodiments of FIGS. 1 through 3, a display device 10includes a cover window 100, a display panel 300, a bracket 600, a maincircuit board 700, and a lower cover 900.

The terms “on”, “top”, and “top surface”, as used herein, may refer toan upward direction from the display device 10, e.g., a Z-axisdirection, and the terms “below”, “bottom” and “bottom surface”, as usedherein, may refer to a downward direction from the display device 10,e.g., the opposite direction of the Z-axis direction. Also, the terms“left”, “right”, “upper”, and “lower”, as used herein, may refer totheir respective directions as viewed from above the display device 10.For example, the terms “left”, “right”, “upper”, and “lower” may referto the opposite direction of an X-axis direction, the X-axis direction,a Y-axis direction, and the opposite direction of the Y-axis direction,respectively.

The display device 10, which is a device for displaying at least onemoving and/or still image, may be used not only in a portable electronicdevice such as a mobile phone, a smartphone, a tablet personal computer(PC), a smartwatch, a watchphone, a mobile communication terminal, anelectronic notepad, an electronic book (e-book), a portable multimediaplayer (PMP), a navigation device, or a ultra-mobile PC (UMPC)), butalso in various other electronic devices such as a television (TV), alaptop computer, a monitor, a billboard, or an Internet-of-Things (IoT)device. However, embodiments of the present inventive concepts are notlimited thereto.

As shown in the embodiment of FIGS. 1-3, the display device 10 may havea rectangular shape in a plan view. For example, the display device 10may have a rectangular shape with relatively shorter sides in a firstdirection (or the X-axis direction) and relatively longer sides in asecond direction (or the Y-axis direction), in a plan view. However,embodiments of the present inventive concepts are not limited thereto.The corners where the relatively shorter sides and the relatively longersides meet may be rounded to have a predetermined curvature or may beright-angled. However, the shape of the display device 10 is notparticularly limited, and the display device 10 may have various othershapes such as a non-tetragonal polygonal shape, a circular shape, or anelliptical shape in a plan view.

The cover window 100 may be disposed on the display panel 300 to coverthe top surface of the display panel 300. The cover window 100 mayprotect the top surface of the display panel 300.

The cover window 100 may include a transmitting area TA, whichcorresponds to (e.g., overlaps in the Z-axis direction) a display areaDA of the display panel 300, and a non-transmitting area NDA, Whichcorresponds to (e.g., overlaps in the Z-axis direction) a non-displayarea NDA of the display panel 300. In an embodiment, thenon-transmitting area NTA may be formed to be opaque. In anotherembodiment, the non-transmitting area NTA may be formed as a decorativelayer having, formed thereon, a pattern that can be seen when an imageis not displayed. However, embodiments of the present inventive conceptsare not limited thereto.

The display panel 300 may be disposed below the cover window 100. Thus,an image displayed by the display panel 300 can be viewed on the topsurface of the display device 10 through the cover window 100.

In an embodiment, the display panel 300 may be a light-emitting displaypanel including light-emitting elements. For example, the display panel300 may be an organic light-emitting diode (OLED) display panel usingOLEDs that include organic light-emitting layers, a micro-light-emittingdiode (mLED) display panel using mLEDs, a quantum-dot light-emittingdiode (QLED) display panel using QLEDs that include quantum-dotlight-emitting layers, or an inorganic light-emitting display panelusing inorganic light-emitting elements that include an inorganicsemiconductor. The display panel 300 will hereinafter be described asbeing, for example, an OLED display panel for convenience ofexplanation. However, embodiments of the present inventive concepts arenot limited thereto.

The display panel 300 may include the display panel DA and thenon-display area NDA.

The display area. DA may overlap with the transmitting area TA of thecover window 100 (e.g., in a Z-axis direction). As shown in theembodiment of FIG. 3, the display area DA may include a plurality ofpixels SP and may display an image. The pixels SP may include firstsubpixels SP1, second subpixels SP2, and third subpixels SP3. In anembodiment, the first subpixels SP1 may emit red light, the secondsubpixels SP2 may emit green light, and the third subpixels SP3 may emitblue light. However, embodiments of the present inventive concepts arenot limited thereto and the number of the pixels SP and the colors thatthe pixels SP emit may vary. In an embodiment, the emission areas or theaperture areas of the first subpixels SP1, the second subpixels SP2, andthe third subpixels SP3 may have different sizes. However, embodimentsof the present inventive concepts are not limited thereto.

The display area DA may include a plurality of fingerprint sensors FPSand may thus be able to recognize a fingerprint of a user. The pixels SPand the fingerprint sensors FPS may be disposed in the same layer of thedisplay panel 300. In an embodiment, each of the fingerprint sensors FPSmay be surrounded by multiple pixels SP. Thus, the display area DA maybe used not only for displaying an image, but also for recognizing theuser's fingerprint. In an embodiment, the fingerprint sensors FPS may bedisposed in the entire display area DA. However, embodiments of thepresent inventive concepts are not limited thereto. For example, thefingerprint sensors FPS may be disposed in only a partial portion of thedisplay area DA.

The non-display area NDA may not display an image. As shown in theembodiments of FIGS. 2-3, the non-display area NDA may be disposedaround the display area DA. In an embodiment, the non-display area NDAmay include a gate driver applying gate signals to gate lines andfan-out lines connecting data lines and a display driver 410. Thenon-display area NDA may surround the display area DA. For example, thenon-display area NDA may completely surround the display area DA (e.g.,in the first and second directions). However, embodiments of the presentinventive concepts are not limited thereto.

In an embodiment, the display panel 300 may include a touch electrodelayer capable of detecting an object such as a finger of the user or apen. The touch electrode layer may include a plurality of touchelectrodes and may be disposed in a display area in which the pixels SPare disposed.

The display panel 300 may further include a sub-area SBA, whichprotrudes from one side of the non-display area NDA. The sub-area SBAmay include a pad portion, which is connected to a circuit board 420.

The sub-area SBA may protrude from one side of the non-display area NDAin the opposite direction of the second direction (or the Y-axisdirection). For example, the length, in the first direction (or theX-axis direction), of the sub-area SBA may be less than the length, inthe first direction (or the X-axis direction), of the display area DA,and the length, in the second direction (or the Y-axis direction), ofthe sub-area SBA may be less than the length, in the second direction(or the Y-axis direction), of the display area DA. However, embodimentsof the present inventive concepts are not limited thereto. The sub-areaSBA may be bendable and may be disposed below the display panel 300. Inthis embodiment, the sub-area SBA may be bent to overlap with thedisplay area DA in the third direction (or the Z-axis direction).

The display panel 300 may include the display driver 410, the circuitboard 420, a power supply 430, and a touch driver 440.

The display driver 410 may be disposed in the sub-area SBA of thedisplay panel 300. The display driver 410 may output signals andvoltages for driving the display panel 300. In an embodiment, thedisplay driver 410 may provide data voltages to the data lines, and thedata voltages may be provided to the pixels SP via the data lines. Thedisplay driver 410 may be connected to the fingerprint sensors FPS viaread-out lines. The display driver 410 may receive sensing signals fromthe fingerprint sensors FPS via the read-out lines. The display driver41.0 may convert the sensing signals into sensing data, which is digitaldata, and may transmit the sensing data to a main processor 710. Thedisplay driver 410 may provide gate control signals to the gate driverand may provide various power supply voltages to power supply lines.

The circuit board 420 may be attached on the pad portion, which isdisposed in the sub-area SBA of the display panel 300. In an embodiment,the circuit board 420 may be attached on the pad portion in the sub-areaSBA of the display panel 300 via a low-resistance, high-reliabilitymaterial such as an anisotropic conductive film (ACF) or a self-assemblyanisotropic conductive paste (SAP). However, embodiments of the presentinventive concepts are not limited thereto and the circuit board 420 maybe attached on the pad portion in the sub-area SBA by various differentmethods. Lead lines of the circuit board 420 may be electricallyconnected to the pad portion of the display panel 300. In an embodiment,the circuit board 420 may be a printed circuit board (PCB), a flexiblePCB (FPCB), or a flexible film such as a chip-on-film (COF).

The power supply 430 may be disposed on the circuit board 420 and maysupply power supply voltages to the display driver 410 and the displaypanel 300. In an embodiment, the power supply 430 may generate a drivingvoltage and may provide the driving voltage to a driving voltage line.For example, the power supply 430 may generate a low-potential voltageand may provide the low-potential voltage to the cathode electrodes oflight-emitting elements of the pixels SP and the cathode electrodes oflight-receiving elements of the fingerprint sensors FPS.

The touch driver 440 may be disposed on the circuit board 420 to measurethe static capacitances of the touch electrodes. In an embodiment, thetouch driver 440 may determine the presence of a touch of the user andthe location of the touch based on variations in the static capacitancesof the touch electrodes. Here, the term “touch”, as used herein, means adirect touch of a finger of the user or an object such as a pen on onesurface of the display device 10, on the touch electrode layer. Thetouch driver 440 may determine the location of the touch of the user bydistinguishing touch electrodes where the touch of the user occurs fromtouch electrodes where the touch of the user does not occur.

As shown in the embodiment of FIG. 2, the bracket 600 may be disposedbelow the display panel 300. In an embodiment, the bracket 600 may beformed of plastic, a metal, or a combination thereof. The bracket 600may include a first camera hole CMH1, in which a first camera sensor 720is inserted, a battery hole BH, in which a battery 790 is disposed, anda cable hole CAH, which a cable 415 may pass therethrough for connectionto the display driver 410 or the circuit board 420.

The main circuit board 700 and the battery 790 may be disposed below thebracket 600. In an embodiment, the main circuit board 700 may be a PCBor an FPCB.

The main circuit board 700 may include the main processor 710, the firstcamera sensor 720, and a main connector 730. The first camera sensor 720may be disposed on both the top and bottom surfaces of the main circuitboard 700. The main processor 710 may be disposed on the top surface ofthe main circuit board 700. The main connector 730 may be disposed onthe bottom surface of the main circuit board 700. However, embodimentsof the present inventive concepts are not limited thereto.

The main processor 710 may control all functions of the display device10. In an embodiment, the main processor 710 may provide digital videodata to the display driver 41.0 so that the display panel 300 maydisplay an image. The main processor 710 may receive sensing data fromthe display driver 410 and generate a fingerprint image, and mayrecognize the pattern of the user's fingerprint. In an embodiment, themain processor 710 may perform authentication or execute an applicationbased on the user's fingerprint. The main processor 710 may receivetouch data from the touch driver 440, may determine the coordinates ofthe touch of the user, and may execute an application pointed to by anicon displayed at the coordinates of the touch of the user. However,embodiments of the present inventive concepts are not limited thereto.

The first camera sensor 720 may process frames of at least one stilland/or moving image obtained by an image sensor and may output theprocessed image frames to the main processor 710. In an embodiment, thefirst camera sensor 720 may be a complementary metal-oxide semiconductor(CMOS) image sensor or a charge-coupled device (CCD) sensor. However,embodiments of the present inventive concepts are not limited thereto.The first camera sensor 720 may be exposed at the bottom surface of thelower cover 900 through a second camera hole CMH2 and may thus be ableto capture an image of an object or the background at the bottom of thedisplay device 10.

The main connector 730 may be connected to the cable 415 through thecable hole CAH of the bracket 600. As a result, the main circuit board700 is electrically connected to the display driver 410 or the circuitboard 420.

In an embodiment, the battery 790 may be disposed not to overlap withthe main circuit board 700 in the third direction (or the Z-axisdirection). The battery 790 may overlap with the battery hole BH of thebracket 600 (e.g., in the third direction).

The lower cover 900 may be disposed below the main circuit board 700 andthe battery 790 (e.g., in the Z-axis direction). The lower cover 900 maybe coupled and fixed to the bracket 600. The lower cover 900 may formthe bottom exterior of the display device 10.

The lower cover 900 may include the second camera hole CMH2, whichexposes the bottom surface of the first camera sensor 720. The locationof the first camera sensor 72.0 and the locations of the first andsecond camera holes CMH1 and CMH2, which correspond to the first camerasensor 720, are not limited to the arrangement shown in FIG. 2.

FIG. 4 is a plan view of a unit pixel area of the display device of FIG.1 according to an embodiment of the present inventive concepts.

Referring to the embodiment of FIG. 4, the display area DA of thedisplay panel 300 may include a plurality of unit pixel areas UPA. Eachof the unit pixel areas UPA may include at least one first subpixel SP1,at least one second subpixel SP2, at least one third subpixel SP3, andat least one fingerprint sensor FPS. In an embodiment, the first,second, and third subpixels SP1, SP2, and SP3 may emit red light, greenlight, and blue light, respectively. However, embodiments of the presentinventive concepts are not limited thereto and the respective colorsemitted by the first, second and third subpixels SP1, SP2, SP3 may vary.As shown in the embodiment of FIG. 4, the first, second, and thirdsubpixels SP1, SP2, and SP3 may be spaced apart from one another (e.g.,in the X-axis and/or Y axis direction) by the fingerprint sensor FPS.Each of the fingerprint sensors FPS may be surrounded by multiple pixelsSP. For example, as shown in the embodiment of FIG. 4, each of the unitpixel areas UPA may include one first subpixel SP1, two second subpixelsSP2, one third subpixel SP3, and four fingerprint sensors FPS However,embodiments of the present inventive concepts are not limited thereto.

In an embodiment, the emission areas or aperture areas of the first,second, and third subpixels SP1, SP2, and SP3, respectively, may havedifferent sizes. For example, in an embodiment, the emission area of thefirst subpixel SN may be larger than the emission area of the thirdsubpixel SP3, and the emission area of the third subpixel SP3 may belarger than the emission area of the second subpixel SP2. The displaypanel 300 can increase the emission efficiency of white light emittedfrom each of the unit pixel areas UPA by controlling the sizes of theemission areas of the first, second, and third subpixeis SP1, SP2, andSP3 of each of the unit pixel areas UPA.

FIG. 5 is a cross-sectional view of the display device of FIG. 1according to an embodiment of the present inventive concepts. FIG. 6 isa cross-sectional view illustrating a thin-film transistor (TFT) layerand a light-emitting element layer of the display device of FIG. 1according to an embodiment of the present inventive concepts.

Referring to the embodiments of FIGS. 5 and 6, the display device 10 mayinclude a substrate SUB, a TFT layer TFTL, a light-emitting elementlayer EML, an encapsulation layer TFEL, a touch sensor layer TSL, andthe cover window 100.

The substrate SUB may be a base substrate or a base member of thedisplay panel 300 and may be formed of an insulating material such as apolymer resin. In an embodiment, the substrate SUB may be a rigidsubstrate. However, embodiments of the present inventive concepts arenot limited thereto and the substrate SUB may be a flexible substratethat is bendable, foldable, or rollable. In an embodiment in which thesubstrate SUB is a flexible substrate, the substrate SUB may includepolyimide (PI). However, embodiments of the present inventive conceptsare not limited thereto.

The TFT layer arm may be disposed on the substrate SUB (e.g., directlythereon in the Z-axis direction). The TFT layer TFTL may include atleast one pixel transistor ST, which is for driving each pixel SP, andat least one sensor transistor FT, which is for driving each fingerprintsensor FPS. The TFT layer TFTL may further include a gate insulatingfilm. GI, an interlayer insulating film ILD, a passivation layer PAS,and a planarization layer OC.

The pixel transistor ST may include a semiconductor region ACT, a sourceelectrode SE, a drain electrode DE, and a gate electrode GE.

The semiconductor region ACT, the source electrode SE, and the drainelectrode DE of the pixel transistor ST may be disposed on the substrateSUB. The semiconductor region ACT of the pixel transistor ST may overlapwith the gate electrode GE of the pixel transistor ST in a thicknessdirection of the substrate SUB and may be insulated from the gateelectrode GE of the pixel transistor ST by the gate insulating film GI.Each of the source electrode SE and the drain electrode DE of the pixeltransistor ST may be obtained by transforming the material of thesemiconductor region ACT of the pixel transistor ST into a conductor.

The gate electrode GE of the pixel transistor ST may be disposed on thegate insulating film GI (e.g., directly thereon in a thickness directionof the substrate SUB). The gate electrode GE of the pixel transistor STmay overlap with the semiconductor region ACT of the pixel transistor STwith the gate insulating film GI interposed therebetween (e.g., in athickness direction of the substrate SUB).

The gate insulating film GI may be disposed on the semiconductor regionACT, the source electrode SE, and the drain electrode DE of the pixeltransistor ST (e.g., directly thereon in a thickness direction of thesubstrate SUB). In an embodiment, the gate insulating film GI may coverthe semiconductor region ACT, the source electrode SE, the drainelectrode DE of the pixel transistor ST, and the substrate SUB and mayinsulate the semiconductor region ACT and the gate electrode GE of thepixel transistor ST. As shown in the embodiment of FIG. 6, the gateinsulating film. GI may include contact holes and the first and secondconnecting electrodes CNE1 and CNE2 may pass through the contact holes.For example, the first connecting electrode CNE1 may pass through acontact hole of the gate insulating film GI for connection with thedrain electrode DE of the semiconductor region ACT of the pixeltransistor ST. The second connecting electrode CNE2 may pass through acontact hole of the gate insulating film GI for connection with thedrain electrode DE of the semiconductor region ACT of the sensortransistor FT.

The sensor transistor FT may include an active area ACT, a sourceelectrode SE, a drain electrode DE, and a gate electrode GE.

The semiconductor region ACT, the source electrode SE, and the drainelectrode DE of the sensor transistor FT may be disposed on thesubstrate SUB (e.g., directly thereon in a thickness direction of thesubstrate SUB). The semiconductor region ACT of the sensor transistor FTmay overlap with the gate electrode GE of the sensor transistor FT inthe thickness direction of the substrate SUB and may be insulated fromthe gate electrode GE of the sensor transistor FT by the gate insulatingfilm GI. Each of the source electrode SE and the drain electrode DE ofthe sensor transistor FT may be obtained by transforming the material ofthe semiconductor region ACT of the sensor transistor FT into aconductor.

The gate electrode GE of the sensor transistor FT may be disposed on thegate insulating film GI (e.g., directly thereon in a thickness directionof the substrate SUB). The gate electrode of the sensor transistor FTmay overlap with the semiconductor region ACT of the sensor transistorFT with the gate insulating film GI interposed therebetween (e.g., in athickness direction of the substrate SUB).

The interlayer insulating film ILD may be disposed on the gateelectrodes GE of the pixel transistor ST and the sensor transistor FT.In an embodiment, the interlayer insulating film ILD may include contactholes and the first and second connecting electrodes CNE1 and CNE2 passthrough the contact holes for connection with the drain electrode DE ofthe semiconductor region ACT of the pixel transistor ST and the drainelectrode DE of the sensor transistor FT, respectively. In anembodiment, the contact holes of the interlayer insulating film ILD maybe connected to the contact holes of the gate insulating film GI.

The first and second connecting electrodes CNE1 and CNE2 may be disposedon the interlayer insulating film ILD and are spaced apart from eachother in a direction parallel to an upper surface of the substrate SUB.The first connecting electrode CNE1 may connect the drain electrode DEof the pixel transistor ST and a pixel electrode PE of a light-emittingelement ED. The first connecting electrode CNE1 may be in contact withthe drain electrode DE of the pixel transistor ST through one of thecontact holes of each of the gate insulating film GI and the interlayerinsulating film ILD.

The second connecting electrode CNE2 may connect the drain electrode DEof the sensor transistor FT and a sensor electrode FPE of alight-receiving element PD. The second connecting electrode CNE2 may bein contact with the drain electrode DE of the sensor transistor FTthrough one of the contact holes of each of the gate insulating film GIand the interlayer insulating film ILD.

The passivation layer PAS may be disposed on the pixel transistor ST andthe sensor transistor FT to protect the pixel transistor ST and thesensor transistor FT. In an embodiment, the passivation layer PAS mayinclude contact holes and the pixel electrode PE of the light-emittingelement ED and the sensor electrode FPE of the light-receiving elementPD pass through the contact holes for connection with the firstconnecting electrode CNE1 and the second connecting electrode CNE2,respectively.

The planarization layer OC may be disposed on the passivation layer PASto planarize the upper surfaces of the pixel transistor ST and thesensor transistor FT. In an embodiment, the planarization layer OC mayinclude contact holes and the pixel electrode PE of the light-emittingelement ED and the sensor electrode FPE of the light-receiving elementPD pass through the contact holes for connection with the firstconnecting electrode CNE1 and the second connecting electrode CNE2,respectively. In an embodiment, the contact holes of the passivationlayer PAS may be connected to the contact holes of the planarizationlayer OC.

The light-emitting element layer EML may be disposed on the TFT layerTFTL (e.g., directly thereon in a thickness direction of the substrateSUB). The light-emitting element layer EMI: may include thelight-emitting element ED, which is connected to the pixel transistorST, and the light-receiving element PD, which is connected to the sensortransistor FT. Thus, the light-emitting element ED and thelight-receiving element PD may be disposed in the same layer and may bespaced apart from each other (e.g., in a direction parallel to an uppersurface of the substrate SUB) by a pixel-defining film PDL.

The light-emitting element ED may include the pixel electrode PE, afirst semiconductor layer NSL, an emission layer EL, a secondsemiconductor layer PSL, and a common electrode CE.

The pixel electrode PE may be disposed on the planarization layer OC, Inan embodiment, the pixel electrode PE may overlap (e.g., in a thicknessdirection of the substrate SUB) with an aperture area of thelight-emitting element layer EML, defined by the pixel-defining filmPDL. The pixel electrode PE may directly contact the first connectingelectrode CNE1 through one of the contact holes of each of theplanarization layer OC and the passivation layer PAS for connection tothe drain electrode DE of the pixel transistor ST. In an embodiment, thepixel electrode PE may function as the anode of the light-emittingelement ED.

The first semiconductor layer NSL may be disposed on the pixel electrodePE. In an embodiment, the first semiconductor layer NSL may be an N-typesemiconductor layer. The N-type semiconductor layer may supply electronsto the emission layer EL. In an embodiment, the first semiconductorlayer NSL may include an electron transport layer and an electroninjection layer. However, embodiments of the present inventive conceptsare not limited thereto.

The emission layer EL may be disposed on the first semiconductor layerNSL. In an embodiment, the emission layer EL may be an organic emissionlayer including an organic material. However, embodiments of the presentinventive concepts are not limited thereto. In an embodiment in whichthe emission layer EL is an organic emission layer, the pixel transistorST may apply a predetermined voltage to the pixel electrode PE of thecommon electrode CE. As the common electrode CE of the light-emittingelement ED receives a cathode voltage or a low-potential voltage, holesand electrons may move to the emission layer EL through the secondsemiconductor layer PSL and the first semiconductor layer NSL and maycombine together in the emission layer EL to emit light.

The second semiconductor layer PSL may be disposed on the emission layerEL. In an embodiment, the second semiconductor layer PSL may be a P-typesemiconductor layer. The P-type semiconductor layer may supply holes tothe emission layer EL. In an embodiment, the second semiconductor layerPSL may include a hole transport layer and a hole injection layer.However, embodiments of the present inventive concepts are not limitedthereto.

The common electrode CE may be disposed on the second semiconductorlayer PSL. The common electrode CE may provide a low-potential voltageto the light-emitting element ED, In an embodiment, the common electrodeCE may be implemented as an electrode that is provided in common for aplurality of pixels SP and a plurality of fingerprint sensors FPS.However, embodiments of the present inventive concepts are not limitedthereto.

The light-receiving element PD may include the sensor electrode FPE, thefirst semiconductor layer NSL, a light-receiving layer PL, the secondsemiconductor layer PSL, and the common electrode CE.

The sensor electrode FPE may be disposed on the planarization layer OC.In an embodiment, the sensor electrode FPE may overlap (e.g., in athickness direction of the substrate SUB) with the aperture area of thelight-emitting element layer EMI, defined by the pixel-defining filmPDL. The sensor electrode FPE may be connected to the second connectingelectrode CNE2 through one of the contact holes of each of theplanarization layer OC and the passivation layer PAS for connection tothe drain electrode DE of the sensor transistor FT.

In an embodiment, the sensor electrode FPE and the pixel electrode PEmay be formed in the same layer using the same material. In anembodiment, the sensor electrode FPE and the pixel electrode PE may beformed as single layers of molybdenum (Mo), titanium (Ti), copper (Cu),or aluminum (Al), stacks of Al and Ti (e.g., Ti/Al/Ti), stacks of Al andindium tin oxide (ITO) (e.g., ITO/Al/ITO), layers of a silver(Ag)-palladium (Pd)-copper (Cu) (APC) alloy, or stacks of an APC alloyand ITO (e.g., ITO/APC/ITO). However, embodiments of the presentinventive concepts are not limited thereto and the material of thesensor electrode FPE and the pixel electrode PE may vary.

The first semiconductor layer NSL of the light-receiving element PD mayshare the first semiconductor layer NSL of the light-emitting elementED. For example, the first semiconductor layer NSL may be disposed onthe pixel-defining film PDL and in an aperture area defined therein andmay be commonly disposed to overlap (e.g., in a thickness direction ofthe substrate SUB) the pixel transistor ST and the sensor transistor FTand form the first semiconductor layer NSL of the light-emitting elementand the first semiconductor layer NSL of the light-receiving element PD,The first semiconductor layer NSL of the light-receiving element PD maybe disposed on the sensor electrode FPE (e.g., directly thereon in athickness direction of the substrate SUB). In an embodiment, the firstsemiconductor layer NSL may be an N-type semiconductor layer. The N-typesemiconductor layer may supply electrons to the light-receiving layerPL. In an embodiment, the first semiconductor layer NSL may include anelectron transport layer and an electron injection layer. However,embodiments of the present inventive concepts are not limited thereto.

The light-receiving layer PL may be disposed on the first semiconductorlayer NSL. The light-receiving layer PL may be depleted by the first andsecond semiconductor layers NSL and PSL, and an electric field may beformed in the Light-receiving layer PL. A second light L2 reflected froma finger F of the user may be incident upon the light-receiving layerPL, and holes and electrons may be drifted by the electric field. Thus,the holes may be collected in the common electrode CE through the secondsemiconductor layer PSL, and the electrons may be collected in thesensor electrode FPE through the first semiconductor layer NSL.

In an embodiment, the second semiconductor layer PSL may be disposedrelatively close to a surface that the second light L2 is incident upon,and the first semiconductor layer NSL may be disposed relatively farfrom the surface that the second light L2 is incident upon. Since thedrift mobility of holes is lower than the drift mobility of electrons,the efficiency of collecting the second light L2 can be maximized bypositioning the second semiconductor layer PSL near the surface that thesecond light L2 is incident upon.

The common electrode C1 may be disposed on the second semiconductorlayer PSL. The common electrode CE may include a transparent conductivematerial capable of transmitting light therethrough. In an embodiment,the common electrode CE may include at least one compound selected fromno, indium zinc oxide (IZO), and indium tin zinc oxide (ITZO). However,embodiments of the present inventive concepts are not limited thereto.

The light-emitting element EML may include the pixel-defining film PDL,which defines a plurality of pixels SP and a plurality of fingerprintsensors FP. Pixel electrodes PE of the plurality of light-emittingelements ED and sensor electrodes FPE of the plurality of fingerprintsensors FPS may be spaced apart (e.g., in a direction parallel to anupper surface of the substrate SUB) and insulated from one another bythe pixel-defining film PDL.

As shown in the embodiments of FIGS. 5-6, as the finger F of the user isin contact with the cover window 100, first light L1 output from thelight-emitting element ED may be reflected by a ridge FR or a valley FVof the finger F, and as a result, the reflected first light, such as thesecond light L2, may reach the light-receiving element PD. The displaydriver 410 may generate sensing data by classifying second light L2reflected from the ridge FR of the finger F and second light L2reflected from the valley FR of the finger F and may transmit thesensing data to the main processor 710. The main processor 710 maygenerate a fingerprint image based on the sensing data and may thusrecognize the pattern of the user's fingerprint.

The encapsulation layer TEEL may be disposed on (e.g., directly thereonin a thickness direction of the substrate SUB) the light-emittingelement layer EML to cover the light-emitting element layer EML. Theencapsulation layer TFEL may prevent oxygen or moisture from penetratinginto the light-emitting element ED and the light-receiving element PD.

The touch sensor layer TSL may be disposed on the encapsulation layerTFEL directly thereon in a thickness direction of the substrate SUB).The touch sensor layer TSL may include touch electrodes for detecting atouch of the user and pads and touch electrodes for connecting pads andthe touch electrodes. In an embodiment, the touch electrodes of thetouch sensor layer TSL may be disposed in a touch sensing area, whichoverlaps with the display area DA of the display panel 300.

The cover window 100 may be disposed on the display panel 300. The coverwindow 100 may be disposed on the touch sensor layer TSL of the displaypanel 300 (e.g., directly on in a thickness direction of the substrateSUB). In an embodiment, the cover window 100 may be attached on thetouch sensor layer TSL via a transparent adhesive member. However,embodiments of the present inventive concepts are not limited thereto. Atop surface of the cover window 100 and the finger F of the user may bein direct contact with each other.

FIG. 7 is a layout view illustrating how the pixels, the fingerprintsensors, and the lines of the display device of FIG. 1 are connected.

Referring to the embodiment of FIG. 7, the display panel 300 may includethe display area DA and the non-display area NDA.

The display area DA may include a plurality of pixels SP, gate lines GLand data lines DL which are connected to the pixels SP, a plurality offingerprint sensors FPS, and sensing lines SL and read-out lines ROL,which are connected to the fingerprint sensors FPS.

Each of the pixels SP may be connected to at least one gate line GL anda data line DL. In an embodiment, each of the pixels SP may includethree gate lines GL and one data line DL. However, embodiments of thepresent inventive concepts are not limited thereto.

Each of the pixels SP may include at least one pixel transistor ST, alight-emitting element ED, and a capacitor. The light-emitting elementED may receive a driving current and emit light in accordance with adata voltage applied to the gate electrode of the pixel transistor ST.For example, the light-emitting element ED may emit light of aparticular luminance in accordance with the driving current.

The pixels SP may be connected to at least one power supply line. Thepixels SP may receive various voltages from the at least one powersupply line. For example, in an embodiment, the pixels SP may receive adriving voltage, an initialization voltage, and a low-potential voltagefrom at least one power supply line. However, embodiments of the presentinventive concepts are not limited thereto.

Each of the fingerprint sensors FPS may be connected to at least onesensing line SL and a read-out line ROL. For example, in an embodiment,each of the fingerprint sensors FPS may be connected to two sensinglines SL and one read-out line ROL. However, embodiments of the presentinventive concepts are not limited thereto.

Each of the fingerprint sensors FPS may include at least one sensortransistor FT, a light-receiving element PD, and a capacitor. Each ofthe fingerprint sensors FPS may receive light and may output a sensingsignal. The fingerprint sensors FPS may provide sensing signals to thedisplay driver 410 via the read-out lines ROL.

The fingerprint sensors FPS may be connected to at least one powersupply line. The fingerprint sensors FPS may receive various voltagesfrom the power supply line. In an embodiment, the fingerprint sensorsmay receive a reset voltage, a common voltage, and a low-potentialvoltage from at least one power supply line. However, embodiments of thepresent inventive concepts are not limited thereto.

As shown in the embodiment of FIG. 7, the gate lines GL and the sensinglines SL may extend in the first direction (or the X-axis direction) andmay be spaced apart from one another in the second direction (or theY-axis direction), which intersects the first direction (or the X-axisdirection). In an embodiment, the gate lines GL and the sensing lines SLmay be formed to extend parallel to each other.

The data lines DL and the read-out lines ROL may be spaced apart fromone another in the first direction (or the X-axis direction) and mayextend in the second direction (or the Y-axis direction). The data linesDL and the read-out lines ROL may be formed to extend parallel to eachother.

In an embodiment, the non-display area NDA may be defined as the entiredisplay panel 300 except 16 r the display area DA. The non-display areaNDA may include the display driver 410, a gate driver 450, fan-out linesFOL, and pads DP.

The display driver 410 may be connected to the pads DP and may receivedigital video data and timing signals. The display driver 410 mayconvert the digital video data into analog data voltages and may providethe analog data voltages to the data lines DL via the fan-out lines FOL.The display driver 410 may receive sensing signals via the read-outlines ROL In an embodiment, the display driver 410 may be formed as anintegrated circuit (IC) and may be mounted on the substrate SUB in achip-on-glass (COG) or chip-on-plastic (COP) manner or via ultrasonicbonding. However, embodiments of the present inventive concepts are notlimited thereto. The display driver 410 may generate gate controlsignals and may provide the gate control signals to the gate driver 450via gate control lines GCL.

The gate driver 450 may be disposed on one side of the non-display areaNDA. For example, as shown in the embodiment of FIG. 7, the gate driver450 may be disposed on the left side of the non-display area NDA (e.g.,in an opposite direction to the X-axis direction). However, embodimentsof the present inventive concepts are not limited thereto. The gatedriver 450 may generate gate signals based on the gate control signalsand may provide the gate signals to the gate lines (IL. The gate linesGL may provide the gate signals to the pixels SP and may select pixelsSP to which data voltages are to be provided.

The gate driver 450 may generate sensing signals based on the gatesignals and may provide the sensing signals to the sensing lines SL. Thesensing lines SL may provide the sensing signals to the fingerprintsensors FPS and may select fingerprint sensors FPS with which to sensethe user's fingerprint.

The fan-out lines FOL may be disposed between the display driver 410 andthe display area DA. For example, as shown in the embodiment of FIG. 7,the display driver 410 may be disposed on a lower side of thenon-display area NDA (e.g., in an opposite direction of the Y-axisdirection) and the fan-out lines FOL may extend between the non-displayarea NDA and the display area DA in the Y direction. However,embodiments of the present inventive concepts are not limited thereto.The fan-out lines FOL may connect the display driver 410 and the datalines DL and may connect the display driver 410 and the read-out linesROL

The pads DP may be disposed more adjacent than the display driver 410 toone edge of the display panel 300. For example, as shown in theembodiment, the pads DP may be disposed between a lower edge of thedisplay panel 300 and the display driver 410 (e.g., in the Y direction).However, embodiments of the present inventive concepts are not limitedthereto. The pads DP may be connected to the circuit board 420.

FIG. 8 is a block diagram illustrating how the gate driver, the pixels,and the fingerprint sensors of the display device of FIG. 1 areconnected.

Referring to the embodiment of FIG. 8, the gate driver 450 may include afirst gate signal supply module 451, a second gate signal supply module452, a third gate signal supply module 453, a first switching elementENT1, and a second switching element ENT2. A gate GL may include first,second, and third gate lines GWL, GIL, and GEL, and a sensing line SLmay include first and second sensing lines RSL and SCL.

The first gate signal supply module 451 may provide a first gate signalGW to the first gate line OWL, The first gate signal OW may be providedto the pixels SP via the first gate line GWL.

The second gate signal supply module 452 may provide a second gatesignal GI to the second gate line GIL. The second gate signal GI may beprovided to the pixels SP via the second gate line GIL.

The third gate signal supply module 453 may provide a third gate signalGB to the third gate line GBL. The third gate signal GB may be providedto the pixels SP via the third gate line GBL. Thus, the pixel SP may bedriven by receiving the first, second, and third gate signals GW, GI,and GB from the first, second, and third gate lines OWL, GIL, and GBL,respectively.

The first switching element ENT1 may be turned on by a reset enablesignal RSEN to connect the first gate line OWL to the first sensing lineRSL. In an embodiment, the first gate signal OW nay have a gate-on levelduring multiple horizontal scanning periods of a single frame so thatthe display device 10 may perform hysteresis compensation on the pixelsSP. In response to the reset enable signal RSEN being received while thefirst gate signal OW has the gate-on level, the first switching elementENT1 may provide a reset signal RST to the first sensing line RSL. In anembodiment, if the first gate signal GW has the gate-on level duringmultiple horizontal scanning periods of a single frame, the reset enablesignal RSEN may be provided to the first switching element ENT1 duringthe final horizontal scanning period. Thus, the first switching elementENT1 may generate an independent reset signal RST from the first gatesignal GW based on the reset enable signal RSEN.

The second switching element ENT2 may be turned on by a scan enablesignal SCE to connect the second gate line GIL to the second sensingline SCL. In an embodiment, the second gate signal GI may have thegate-on level during multiple horizontal scanning periods of a singleframe so that the display device 10 may perform hysteresis compensationon the pixels SR In response to the scan enable signal SCEN beingreceived while the second gate signal GI has the gate-on level, thesecond switching element ENT2 may provide a scan signal SC to the secondsensing line SCL. In an embodiment, if the second gate signal CH has thegate-on level during multiple horizontal scanning periods of a singleframe, the scan enable signal SCEN may be provided to the secondswitching element ENT2 during the final horizontal scanning period.Thus, the second switching element ENT2 may generate an independent scansignal SC from the second gate signal GI based on the scan enable signalSCEN.

The pixels SP and the fingerprint sensors FPS may be disposed in thesame layer, e.g., in the light-emitting element layer EML, and thedisplay driver 410 and the gate driver 450 may drive the pixels SP andthe fingerprint sensors FPS. The gate driver 450 may drive the pixels SPbased on the first, second, and third gate signals GW, GI, and GB. Sinceat least one of the first, second, and third gate signals GW, GI, andGB, such as the first and second gate signals GW, GI, have a gate-onlevel during multiple horizontal scanning periods of a single frame, thedisplay device 10 may perform hysteresis compensation on the pixels SP.The gate driver 450 can generate the reset signal RST and the scansignal SC, which are independent from the first and second gate signalsGW and GI, respectively, using the first and second switching elementsENT1 and ENT2, respectively. Accordingly, by providing the reset signalRST and the scan signal SC, which are independent from the first andsecond gate signals GW and GI, respectively, to the fingerprint sensorsFPS, the gate driver 450 can increase the duration of exposure of thefingerprint sensors FPS to light, even when the display device 10 isperforming hysteresis compensation, and can increase the sensitivity ofthe fingerprint sensors FPS.

FIG. 9 is a circuit diagram of a pixel of the display device of FIG. 1.

Referring to FIG. 9, a pixel SP may be connected to the first gate lineGWL, the second gate line GIL, the third gate line GBL, an emissioncontrol line EML, a data line DL, driving voltage line VDDL, and aninitialization voltage line VIL.

As shown in the embodiment of FIG. 9, the pixel SP may include alight-emitting element ED, first through seventh pixel transistors ST1through ST7, and a first capacitor C1. However, embodiments of thepresent inventive concepts are not limited thereto.

The first pixel transistor ST1 may include a gate electrode, a sourceelectrode, and a drain electrode. The source electrode of the firstpixel transistor ST1 may be connected to a first node N1, the drainelectrode of the first pixel transistor ST1 may be connected to a secondnode N2, and the gate electrode of the first pixel transistor ST1 may beconnected to a third node N3. In an embodiment, the first pixeltransistor ST1 may control a source-drain current ID (hereinafter, thedriving current II)) in accordance with a data voltage Vdata applied tothe gate electrode of the first pixel transistor ST1.

The light-emitting element ED may receive the driving current ID and maythereby emit light. The amount of light emitted by the light-emittingelement ED or the luminance of the light-emitting element ED may beproportional to the magnitude of the driving current ID.

In an embodiment, the light-emitting element ED may be an OLED includinga first electrode, a second electrode, and an organic light-emittinglayer between the first and second electrodes. However, embodiments ofthe present inventive concepts are not limited thereto. For example, thelight-emitting element ED may be an inorganic light-emitting elementincluding a first electrode, a second electrode, and an inorganicsemiconductor between the first and second electrodes. Thelight-emitting element ED may be a quantum-dot light-emitting elementincluding a first electrode, a second electrode, and a quantum-dotlight-emitting layer between the first and second electrodes. Thelight-emitting element ED may be an mLED.

The first electrode or the anode of the light-emitting element ED may beconnected to a fourth node N4, The first electrode of the light-emittingelement ED may be connected do the drain electrodes of the sixth andseventh pixel transistors ST6 and ST7 via the fourth node N4, The secondelectrode of the light-emitting element ED may be connected to alow-potential line VSSL. Parasitic capacitance may be formed between thefirst and second electrodes of the light-emitting element ED.

The second pixel transistor ST2 may be turned on by the first gatesignal GW from the first gate line GWL to connect the data line DL andthe first node N1, which is the source electrode of the first pixelelectrode ST1. The second pixel transistor ST2 may be turned on by thefirst gate signal GW to provide the data voltage Vdata to the first nodeN1. As shown in the embodiment of FIG. 9, the gate electrode of thesecond pixel transistor ST2 may be connected to the first gate line GWL,the source electrode of the second pixel transistor ST2 may be connectedto the data line DL, and the drain electrode of the second pixeltransistor ST2 may be connected to the first node N1. The drainelectrode of the second pixel transistor ST2 may be connected to thesource electrode of the first pixel transistor ST1 and the drainelectrode of the fifth pixel transistor ST5 via the first node N1.

The third pixel transistor ST3 may be turned on by the first gate signalGW from the first gate line OWL to connect the second node N2, which isthe drain electrode of the first pixel transistor ST1, and the thirdnode N3, which is the gate electrode of the first pixel transistor ST1,The gate electrode of the third pixel transistor ST3 may be connected tothe first gate line OWL, the source electrode of the third pixeltransistor ST3 may be connected to the second node N2, and the drainelectrode of the third pixel transistor ST3 may be connected to thethird node N3. The source electrode of the third pixel transistor ST3may be connected to the drain electrode of the first pixel transistorST1 and the source electrode of the sixth pixel transistor ST6 via thesecond node N2. The drain electrode of the third pixel transistor ST3may be connected to the gate electrode of the first pixel transistorST1, the drain electrode of the fourth pixel transistor ST4, and thefirst electrode of the first capacitor C1 via the third node N3.

The fourth pixel transistor ST4 may be turned on by the second gatesignal GI from the second gate line GIL to connect the initializationvoltage line VIL and the third node N3, which is the gate electrode ofthe first pixel transistor ST1. The fourth pixel transistor ST4 may beturned on by the second gate signal GI to discharge the gate electrodeof the first pixel transistor ST1 to an initialization voltage. The gateelectrode of the fourth pixel transistor ST4 may be connected to thesecond gate line GIL, the source electrode of the fourth pixeltransistor ST4 may be connected to the initialization voltage line VIL,and the drain electrode of the fourth pixel transistor ST4 may beconnected to the third node N3. The drain electrode of the fourth pixeltransistor ST4 may be connected to the gate electrode of the first pixeltransistor ST1, the drain electrode of the third pixel transistor ST3,and the first electrode of the first capacitor C1 via the third node N3.

The fifth pixel transistor ST5 may be turned on by an emission signalfrom the emission control line EMI, to connect the driving voltage lineVDDL and the first node N1, which is the source electrode of the firstpixel transistor ST1 The gate electrode of the fifth pixel transistorST5 may be connected to the emission control line EML, the sourceelectrode of the fifth pixel transistor ST5 may be connected to thedriving voltage line VDRL, and the drain electrode of the fifth pixeltransistor ST5 may be connected to the first node N1. The drainelectrode of the fifth pixel transistor ST5 may be connected to thesource electrode of the first pixel transistor ST1 and the drainelectrode of the second pixel transistor ST2 via the first node N1.

The sixth pixel transistor ST6 may be turned on by the emission signalfrom the emission control line EML to connect the second node N2, whichis the drain electrode of the first pixel transistor ST1, and the fourthnode N4, which is the first electrode of the light-emitting element ED.The gate electrode of the sixth pixel transistor ST6 may be connected tothe emission control line EML, the source electrode of the sixth pixeltransistor ST6 may be connected to the second node N2, and the drainelectrode of the sixth pixel transistor ST6 may be connected to thefourth node N4. The source electrode of the sixth pixel transistor ST6may be connected to the drain electrode of the first pixel transistorST1 and the source electrode of the third pixel transistor ST3 via thesecond node N2. The drain electrode of the sixth pixel transistor ST6may be connected to the first electrode of the light-emitting element EDand the drain electrode of the seventh pixel transistor ST7 via thefourth node N4.

In an embodiment in which the fifth pixel transistor ST5, the firstpixel transistor ST1, and the sixth pixel transistor ST6 are all turnedon, the driving current ID may be provided to the light-emitting elementED.

The seventh pixel transistor ST7 may be turned on by the gate signal GBfrom the third gate line GBL to connect the initialization voltage lineVIL and the fourth node N4, which is the first electrode of thelight-emitting element ED. The seventh pixel transistor ST7 may beturned on by the gate signal GB to discharge the first electrode of thelight-emitting element ED to the initialization voltage. The gateelectrode of the seventh pixel transistor ST7 may be connected to thethird gate line GBL, the source electrode of the seventh pixeltransistor ST7 may be connected to the initialization voltage line VIL,and the drain electrode of the seventh pixel transistor ST7 may beconnected to the fourth node N4. The drain electrode of the seventhpixel transistor ST7 may be connected to the first electrode of thelight-emitting element ED and the drain electrode of the sixth pixeltransistor ST6 via the fourth node N4.

In an embodiment, each of first through seventh pixel transistors ST1through ST7 may include a silicon (Si)-based active layer. For example,each of the first through seventh pixel transistors ST1 through ST7 mayinclude a low-temperature polycrystalline silicon (LTPS)-based activelayer. The LIPS-based active layer may have excellent electron mobilityand excellent turn-on characteristics. As the display device 10 includesthe first through seventh pixel transistors ST1 through ST7 withexcellent turn-on characteristics in each of a plurality of pixels SP,the display device 10 can drive the plurality of pixels SP stably andefficiently.

In an embodiment, the first through seventh pixel transistors ST1through ST7 may be p-type pixel transistors. For example, the firstthrough seventh transistors ST1 through ST7 may output a current inputto their source electrodes to their drain electrodes based on a gate-lowvoltage applied to their gate electrodes.

The capacitor C1 may be connected between the third node N3, which isthe gate electrode of the first pixel transistor ST1, and the drivingvoltage line VDDL. In an embodiment, the first electrode of thecapacitor C1 may be connected to the third node N3, and the secondelectrode of the capacitor C1 may be connected to the driving voltageline VDDL. However, embodiments of the present inventive concepts arenot limited thereto. Accordingly, the difference in electric, potentialbetween the driving voltage line VDDL and the gate electrode of thefirst pixel transistor ST1 can be maintained.

FIG. 10 is a circuit diagram of a fingerprint sensor of the displaydevice of FIG. 1.

Referring to FIG. 10, a fingerprint sensor FPS may be connected to thefirst sensing line RSL, the second sensing line SCL, and the read-outline ROL.

The fingerprint sensor FPS may include first, second, and third sensortransistors FT1, FT2, and FT3, a light-receiving element PD, and asecond capacitor C2.

The first sensor transistor FT1 may be turned on by the voltage of afirst node N1 to provide a common voltage VCOM to a second node N2. Thegate electrode of the first sensor transistor FT1 may be connected tothe first node N1, the source electrode of the first sensor transistorFT1 may be connected to a common voltage line VCL, and the drainelectrode of the first sensor transistor FT1 may be connected to thesecond node N2. The first sensor transistor FT1 may control asource-drain current IS (hereinafter, the sensing current IS) based onthe voltage of the first node N1, which is the first electrode of thelight-receiving element PD. The sensing current IS, which flows throughthe channel of the first sensor transistor FT1, may be proportional tothe square of the difference between a voltage Vsg, which is the voltagebetween the source and gate electrodes of the first sensor transistorFT1, and a threshold voltage Vth between the source electrode and thegate electrode of the first sensor transistor FT1. For example, in anembodiment, the sensing current IS may be determined by the followingequation: IS=k′×(Vsg−Vth)² where k′ is a proportionality coefficientdetermined by the structure and physical characteristics of the firstsensor transistor FT1, Vsg is the source-gate voltage of the firstsensor transistor FT1, and Vth is the threshold voltage of the firstsensor transistor FT1. The sensing current IS of the first sensortransistor FT1 may be provided to the read-out line ROL as a sensingsignal through the second sensor transistor FT2.

The second sensor transistor FT2 may be turned on by a scan signal SCfrom the second sensing line SCL to connect the second node N2, which isthe drain electrode of the first sensor transistor FT1, and the read-outline ROL. The gate electrode of the second sensor transistor FT2 may beconnected to the second sensing line SCL, the source electrode of thesecond sensor transistor FT2 may be connected to the second node N2, andthe drain electrode of the second sensor transistor FT2 may be connectedto the read-out line ROL.

The third sensor transistor FT3 may be turned on by the reset signal RSTfrom the first sensing line RSL to provide a reset voltage VRST to thefirst node N1. The third sensor transistor FT3 may be turned on by thereset signal RST to reset the first node N1, which is the gate electrodeof the first sensor transistor FT1. The gate electrode of the thirdsensor transistor FT3 may be connected to the first sensing line RSL,the source electrode of the third sensor transistor FT3 may be connectedto a reset voltage line and the drain electrode of the third sensortransistor FT3 may be connected to the first node N1.

The light-receiving element PD may recognize the pattern of the user'sfingerprint based on the second light L2 (FIG. 5), which is reflectedlight from the finger F of the user. The first electrode of thelight-receiving element P1) may be connected to the first node N1, whichis the gate electrode of the first sensor transistor FT1, and the secondelectrode of the light-receiving element P11) may be connected to thelow-potential line VSSL. The second electrode of the light-receivingelement PD may receive a low-potential voltage from the low-potentialline VSSL. The second electrode of the light-receiving element PD mayreceive the same low-potential voltage as the second electrode of thelight-emitting element ED. The second capacitor C2 is disposed betweenthe first and second electrodes of the light-receiving to element PD andcan prevent an excessive current in the light-receiving element PD.

As shown in the embodiment of FIG. 5, in response to the finger F of theuser being placed on, and in contact with the cover window 100, thelight-receiving element PD may receive the second light L2, which isreflected light from a ridge FR or valley FV of the finger F, The firstlight L1, which is output from the light-emitting element layer EML, maybe reflected by the ridges FR or the valleys FV of the finger F, and thereflected first light, such as the second light L2, may reach thelight-receiving element P1). The light-receiving element PD may convertthe energy of the second light L2 into an electrical signal (e.g., acurrent or a voltage) formed between the first and second electrodesthereof, and the electrical signal may flow from the first node N1 tothe low-potential line VSSL.

The display driver 410 may generate sensing data based on the sensingsignal from the fingerprint sensor FPS, and the main processor 710 mayrecognize the pattern of the user's fingerprint by determining whetherthe sensing data corresponds to a ridge FR or a valley FV of the fingerF.

In an embodiment, the light-receiving element PD may be implemented as aphototransistor or a photodiode. However, embodiments of the presentinventive concepts are not limited thereto. The light-receiving elementPD may correspond to an optical sensor that converts light energy intoelectrical energy and may use a photovoltaic effect, in which a currentvaries in accordance with the intensity of light.

FIG. 11 is a waveform view of signals applied to the pixel of FIG. 9 andthe fingerprint sensor of FIG. 10.

Referring to the embodiment FIG. 11, the first, second, and third gatelines OWL, GIL, and GBL may provide the first, second, and third gatesignals GW, GI, and GB, respectively. The first and second sensing linesRSL and SCL may provide the reset signal RST and the scan signal SC,respectively.

A frame may include first through sixth periods t1 through t6. Each ofthe first through sixth periods t1 through t6 may include at least onehorizontal scanning period. In an embodiment, each of the first, third,fourth, and fifth periods t1, t3, t4, and t5 may include one horizontalscanning period, the second period t2 may include three horizontalscanning periods, and the sixth period t6 may include more horizontalscanning periods than the second period t2.

As at least one of the first, second, and third gate signals GW, GI, andGB, such as the first and second gate signals GW, GI, have a gate-onlevel during multiple horizontal scanning periods of a single frame(e.g., a first frame “Frame 1”), the display device 10 can performhysteresis compensation on multiple pixels SP.

In an embodiment in which the first gate signal OW has the gate-on levelduring multiple horizontal scanning periods of the first frame “Frame1”, the reset enable signal RSEN may be provided to the first switchingelement ENT1 during the final horizontal scanning period of the firstframe “Frame 1”. For example, in an embodiment, a first gate signal.GW[N], which is to be provided to a first gate line GWL for an N-th row(where N is a natural number), may have the gate-on level three timesduring the second and fourth periods t2 and t4. The gate driver 450 mayprovide the reset enable signal RSEN during the fourth and fifth periodst4 and t5. Thus, the first switching element ENT1 may generate a resetsignal RST(N) having the gate-on level during the fourth period t4,based on the reset enable signal RSEN. The first switching element ENT1may generate an independent reset signal RST(N) from the first gatesignal GW[N] based on the reset enable signal RSEN.

In an embodiment in which the second gate signal GI has the gate-onlevel during multiple horizontal scanning periods of the first frame“Frame 1.”, the scan enable signal SCEN may be provided to the secondswitching element ENT2 during the final horizontal scanning period ofthe first frame “Frame 1”, For example in an embodiment, a second gatesignal GI[N], which is to be provided to a second gate line GIL for theN-th row, may have the gate-on level three times during the first,second, and third periods t1, t2, and t3. The gate driver 450 mayprovide the scan enable signal SCEN during the third and fourth periodst3 and t4, Thus, the second switching element ENT2 may generate a scansignal SC(N) having the gate-on level during the third period t3, basedon the scan enable signal SCEN. The second switching element ENT2 maygenerate an independent scan signal SC(N) from the second gate signalGI[N] based on the scan enable signal SCEN.

The first and second gate signals OW and GI may have the gate-on levelover a plurality of frames, and the reset enable signal RSEN and thescan enable signal SCEN may have the gate-on level over at least oneframe of the plurality of frames. Thus, the display device 10 can selecta frame in which to drive a plurality of fingerprint sensors FPS fromamong the plurality of frames, even when a plurality of pixels SP are tobe driven over the plurality of frames.

The pixels SP and the fingerprint sensors FPS may be disposed in thelight-emitting element layer EML, and the display driver 410 and thegate driver 450 may drive the pixels SP and the fingerprint sensors FPS,The gate driver 450 may drive the pixels SP based on the first, second,and third gate signals OW, GI, and GB. As at least one of the first,second, and third gate signals GW, GI, and GB, such as the first andsecond gate signals GW, GI, has the gate-on level during multiplehorizontal scanning periods of a single frame, the display device 10 canperform hysteresis compensation on the pixels SR The gate driver 450 maygenerate an independent reset signal RST and an independent scan signalSC from the first and second gate signals OW and GI, using the first andsecond switching elements ENT1 and ENT2. Thus, the gate driver 450provides the reset signal RST and the scan signal SC, which areindependent from the first and second gate signals OW and GI, to thefingerprint sensors FPS and can thus increase the duration of exposureof the fingerprint sensors FPS to light, such as EIT[N], and increasethe sensitivity of the fingerprint sensors FPS even when the displaydevice 10 is performing hysteresis compensation.

What is claimed is:
 1. A display device comprising: a display panelcomprising a plurality of pixels connected to gate lines and data lines,and a plurality of fingerprint sensors connected to sensing lines andread-out lines; and a gate driver providing gate signals to the gatelines and providing sensing signals to the sensing lines, wherein thegate driver comprises: a first gate signal supply module providing afirst gate signal to a first gate line among the gate lines; and a firstswitching element turned on by a reset enable signal to connect thefirst gate line and a first sensing line among the sensing lines.
 2. Thedisplay device of claim 1, wherein in response to the reset enablesignal being received when the first gate signal has a gate-on level,the first switching element provides a reset signal to the first sensingline.
 3. The display device of claim 2, wherein; the first gate signalhas the gate-on level during a plurality of horizontal scanning periodsof a single frame; and the reset enable signal is provided to the firstswitching element during a final horizontal scanning period of theplurality of horizontal scanning periods.
 4. The display device of claim2, wherein: the first gate signal has the gate-on level over a pluralityof frames, and the reset enable signal is provided to the firstswitching element over at least one frame of the plurality of frames. 5.The display device of claim 2, wherein the gate driver furthercomprises: a second gate signal supply module providing a second gatesignal to a second gate lime among the gate lines; and a secondswitching element turned on by a scan enable signal to connect thesecond gate line to a second sensing line among the sensing lines. 6.The display device of claim 5, wherein in response to the scan enablesignal being received when the second gate signal has a gate-on level,the second switching element provides a scan signal to the secondsensing line.
 7. The display device of claim 6, wherein: the second gatesignal has the gate-on level during a plurality of horizontal scanningperiods of a single frame; and the scan enable signal is provided to thesecond switching element during a final horizontal scanning period ofthe plurality of horizontal scanning periods.
 8. The display device ofclaim 6, wherein each of the plurality of fingerprint sensors comprises:a light-receiving element; a first node that is a first electrode of thelight-receiving element; a first sensor transistor providing a commonvoltage to a second node based on a voltage of the first node; a secondsensor transistor selectively connecting the second node and one of theread-out lines; and a third sensor transistor selectively providing areset voltage to the first node.
 9. The display device of claim 8,wherein: the second sensor transistor is turned on by the scan signal;and the third sensor transistor is turned on by the reset signal. 10.The display device of claim 1, wherein each of the plurality of pixelscomprises: a light-emitting element; a first pixel transistorcontrolling a driving current that is provided to the light-emittingelement; a second pixel transistor selectively providing a data voltageto a first node, the first node is a first electrode of the first pixeltransistor; a third pixel transistor selectively connecting a secondRode and a third node, the second node is a second electrode of thefirst pixel transistor, and the third node is a gate electrode of thefirst pixel transistor; and a fourth pixel transistor selectivelyproviding an initialization voltage to the third node.
 11. The displaydevice of claim 10, wherein: the second and third pixel transistors areturned on by the first gate signal; and the fourth pixel transistor isturned on by a second gate signal.
 12. The display device of claim 10,wherein each of the plurality of pixels further comprises: a fifth pixeltransistor selectively providing a driving voltage to the first node; asixth pixel transistor selectively connecting the second node and afourth node, the fourth node is a first electrode of the light-emittingelement; and a seventh pixel transistor selectively providing theinitialization voltage to the fourth node.
 13. The display device ofclaim 1, wherein the plurality of pixels comprise first, second, andthird pixels emitting light of different colors, the display panelcomprises a plurality of unit pixel areas, and each of the plurality ofunit pixel areas comprises at least one of each of the first, second,and third pixels and at least one fingerprint sensor.
 14. The displaydevice of claim 1, wherein the display panel comprises: a substrate; athin-film transistor (TFT) layer disposed on the substrate; and alight-emitting element layer disposed on the thin-film transistor layer,the thin-film transistor layer comprises: a gate insulating filmdisposed on the substrate; and an interlayer insulating film disposed onthe gate insulating film, and each of the plurality of pixels include alight-emitting element and each of the plurality of fingerprint sensorsincludes a light-receiving element, the light-emitting elements and thelight-receiving elements are disposed in the light-emitting elementlayer.
 15. The display device of claim 14, wherein each of the pluralityof pixels comprises: a pixel transistor including an active area, asource electrode, and a drain electrode that are disposed on thesubstrate; the pixel transistor further includes a gate electrodedisposed on the gate insulating film; and a first connecting electrodeis disposed on the interlayer insulating film and is connected to thedrain electrode of the pixel transistor.
 16. The display device of claim15, wherein each of the light-emitting elements comprises: a pixelelectrode disposed on the thin-film transistor layer and connected tothe first connecting electrode; a light-emitting layer disposed on thepixel electrode; and a common electrode disposed on the light-emittinglayer.
 17. The display device of claim 14, wherein each of the pluralityof fingerprint sensors comprises: a sensor transistor including anactive area, a source electrode, and a drain electrode that are disposedon the substrate; the sensor transistor further includes a gateelectrode disposed on the gate insulating film; and a second connectingelectrode is disposed on the interlayer insulating film and is connectedto the drain electrode of the sensor transistor.
 18. The display deviceof claim 17, wherein each of the light-receiving elements comprises: asensor electrode disposed on the thin-film transistor layer andconnected to the second connecting electrode; a light-receiving layerdisposed on the sensor electrode; and a common electrode disposed on thelight-receiving layer.
 19. The display device of claim 1, wherein thedisplay panel further comprises a display driver providing data voltagesto the data lines and receiving sensing signals from the read-out lines.20. The display device of claim 1, wherein: the gate lines and thesensing lines extend in a first direction and are spaced apart from oneanother in a second direction intersecting the first direction; and thedata lines and the read-out lines extend in the second direction and arespaced apart from one another in the first direction.
 21. A displaydevice comprising: a display panel comprising a plurality of pixelshaving light-emitting elements and a plurality of fingerprint sensorshaving light-receiving elements; the light-emitting elements and thelight-receiving elements are disposed in a light-emitting element layerand are spaced apart from each other by a pixel defining film; and agate driver providing gate signals to the plurality of pixels andsensing signals to the plurality of fingerprint sensors; wherein thegate driver provides at least one gate signal having a gate-on levelduring a plurality of horizontal scanning periods of a single frame, andthe gate driver provides at least one of a reset signal and a scansignal to the plurality of fingerprint sensors for activating thelight-receiving elements, the at least one reset signal and scan signalare independent from the at least one gate signal.